INCORPORATING STARCHES H ave you ever tried adding flour or cornstarch directly to a hot soup in an attempt to thicken it, only to find that the starch clumps up into frustratingly impossible-to-destroy little balls? Here’s the problem, and it has to with the nature of the interaction between starch—a complex carbohydrate found in all sorts of plant matter, including flour—and water Remember those little dinosaur-shaped sponges you’d get as a kid, which you’d drop into water, then wait for them to grow? That’s exactly what starch molecules are like When dry, they are tiny and shriveled They can flow freely past each other But expose them to water, and they start growing, getting bigger and bigger, until they eventually rub up against each other and bind, creating a water-resistant barrier Are you starting to get the picture? When a spoonful of flour or cornstarch lands on the surface of a pot of water or milk, the first parts to get wet are the starches on the outside of the granules, which rapidly expand, forming a waterproof seal As you stir and submerge the clumps, a seal ends up forming around the entire clump, keeping the interior from getting wet So, how do you solve this problem? Two ways With a starch that doesn’t need to be cooked before it is incorporated (such as cornstarch or potato starch), just dissolve the starch in a small amount of liquid to start Starting with a smaller amount of liquid makes the mechanical stirring action of your spoon, fork, or whisk much more effective Smaller amounts of liquid also get viscous more easily, making it simpler to bash up those pockets of dry starch I use an equal volume of starch to liquid to start and stir it until homogeneous before adding the remaining liquid, or adding it to the rest of the liquid For starches that need to have their raw flavor cooked out of them, such as flour, start them in fat Starch does not swell in fat, so by first combining flour with a fat like butter or oil and mixing it until homogeneous, you end up coating the individual starch granules, preventing them from swelling and sticking together when you first add the liquid After you add it, the fat eventually melts away, so the starch is exposed and can be incorporated smoothly This is the premise behind using a roux to thicken a soup or sauce Finally, remember that for starches to thicken properly, they must be brought to a complete boil to reach their optimal swelling size You’ll notice a soup thicken dramatically as it goes from just plain hot to actually boiling HOW TO BUY BROCCOLI AND CAULIFLOWER ... starch to liquid to start and stir it until homogeneous before adding the remaining liquid, or adding it to the rest of the liquid For starches that need to have their raw flavor cooked out of them, such as flour, start them in fat Starch does... end up coating the individual starch granules, preventing them from swelling and sticking together when you first add the liquid After you add it, the fat eventually melts away, so the starch is exposed and can be incorporated smoothly... before it is incorporated (such as cornstarch or potato starch), just dissolve the starch in a small amount of liquid to start Starting with a smaller amount of liquid makes the mechanical stirring